1. Field of the Invention
The present invention relates to a lens-fitted photographic film unit which has a photographic film contained therein and is equipped with a taking lens and a shutter mechanism.
2. Description of the Prior Art
Lens-fitted photographic film units (hereinafter referred to simply as film units) have been widely used due to their simplicity. Such film units can be purchased at nearly any store, and it is possible to take photographs instantly without making any advance preparation. After all frames of such a film unit are exposed, the film unit is forwarded to a photofinishing laboratory. In the photofinishing laboratory, the exposed photographic film is removed from the film unit and subjected to developing and printing processes. Then, the developed photographic film and resultant photoprints are returned to the customer. In these circumstances, it is necessary to make the film units as inexpensively as possible. At present, the film housing of the film unit, which contains a photographic film and is equipped with a taking lens and a shutter mechanism, is formed of plastic and encased in an outer casing formed of cardboard. The outer casing is formed with openings to expose the taking lens, a rear finder window, a front finder window, a shutter release button, a flash window, a film advancing wheel, etc. Therefore, it is possible to take photographs without ever removing the film housing from the outer casing.
Thus, when taking photographs, the shutter release button is depressed through the corresponding opening of the outer casing. If an object is low in brightness, the shutter release button is depressed only after a flash device is first charged by depressing a flash button. The outer casing is provided with a channel-shaped slit whose shape corresponds to the outline of the flash button, so that the flash button can be depressed with ease by pushing down on the overlying portion of the outer casing. These buttons are formed integrally with a front cover which is a part of the film housing. The front cover has a channel-shaped slit, and a tongue-shaped area surrounded by the slit serves as the flash button. According to this construction, there is no need to incorporate a separate part for the flash button into the film housing, and also there is no need to incorporate a spring for returning the flash button to its initial position since the plastic of the tongue-shaped area has inherent elasticity.
Since the flash button is formed by providing the slit in the front cover as mentioned above, the flash button at its initial position is located in the same plane as the outer surface of the front cover. Accordingly, for example when carrying the film unit in a bag, there is a danger that other articles in the bag may collide with the flash button and cause unintended depression of the flash button. In such a case, charging occurs, which runs down the dry-cell battery. When the shutter release button is formed in the same manner as the flash button, it is subject to the same unintended actuation.